<!DOCTYPE html>
<html>
<head>
<style type="text/css">
.box {position: relative; left:50px; top: 50px; outline: red dotted 1px;width: 200px; height:200px;}
.lc {position: absolute; left:0px; top:0px;border: green dotted 1px;width: 20px; height:20px;}
.rc {position: absolute; right:0px; top:0px;border: blue dotted 1px;width: 20px; height:20px;}
.brc {position: absolute; right:0px; bottom:0px;border: blue dotted 1px;width: 20px; height:20px;}
</style>
</head>
<body>
<div class="box">
  <div class="border">
    <div class="lc"></div>
    <div class="brc"></div>
  </div>
</div>
</div>
</body>
</html>
